Anastrozole (Arimidex) is suitable for women who have been through menopause and whose breast cancer is oestrogen receptor positive.

Anastrozole (Arimidex) is sometimes given alongside ovarian suppression to women who haven’t yet been through their menopause. If your cancer is hormone receptor negative, then Anastrozole (Arimidex) will not be of any benefit.

Anastrozole (Arimidex) may be given to reduce a risk of breast cancer in women who haven’t had breast cancer but have an increased risk of developing it because of their family history.

How Anastrozole (Arimidex) works

Anastrozole (Arimidex) works by reducing the amount of oestrogen made in your body.

When is Anastrozole (Arimidex) given?

Anastrozole (Arimidex) is usually given after surgery to reduce a risk of breast cancer coming back or spreading.

If you’re having chemotherapy or radiotherapy, your specialist will tell you when it’s the best time to start Anastrozole (Arimidex).

Occasionally, Anastrozole (Arimidex) may be used as the first treatment for breast cancer, for example when surgery isn’t appropriate or needs to be delayed. It’s sometimes given before surgery to shrink a large breast cancer.

Anastrozole (Arimidex) can also be used to treat breast cancer that has come back (recurrence). It can also be given to treat breast cancer that has spread to another part of your body (secondary breast cancer), when it’s often given alongside another drug.

How is Anastrozole (Arimidex) given?

Anastrozole (Arimidex) is taken as a tablet once a day, with or without food. It’s the best to take it at the same time every day.

If you miss a dose, you don’t need to take an extra dose the next day. The level of drug in your body will remain high enough from the day before.

Some brands of Anastrozole (Arimidex) contain small amounts of lactose. If you know you are lactose intolerant, discuss this with your treatment team or pharmacist.

How long is Anastrozole (Arimidex) given for?

The recommended length of time that Anastrozole (Arimidex) is taken for will depend on your individual situation.

People being treated for primary breast cancer will usually take Anastrozole (Arimidex) for five to ten years.

Some people start taking Anastrozole (Arimidex) after a number of years of taking another hormone therapy drug called Tamoxifen.

If you’re taking Anastrozole (Arimidex) to treat breast cancer that has come back or spread to another part of your body, you’ll usually take it for as long as it’s effective and any side effects can be managed.

If you’re taking Anastrozole (Arimidex) to reduce a risk of breast cancer developing because of your family history, you’ll usually take it for five years.

Stopping taking Anastrozole (Arimidex)

Your treatment team will tell you when to stop taking Anastrozole (Arimidex). You won’t need to stop taking it gradually.

Some people worry about stopping their treatment, but there’s evidence that Anastrozole (Arimidex) continues reducing a risk of breast cancer coming back for many years after you stop taking it.

However, not taking the drug for the recommended time may increase the risk of your breast cancer coming back. If you’re thinking about stopping taking Anastrozole (Arimidex) for any reason, talk to your specialist first. Sometimes, it may be possible to change to another hormone therapy.

Taking Anastrozole (Arimidex) with other drugs

If you’re taking any other prescribed or over-the-counter medicines, check with your treatment team or pharmacist if you can take these with Anastrozole (Arimidex).

Do not take other drugs containing oestrogen, such as hormone replacement therapy (HRT), while you’re taking Anastrozole (Arimidex) as this may interfere with its effectiveness.

Please remember the information given above is just a summary. Your doctor can provide more information about Anastrozole (Arimidex). Do not share this medicine with the others who it was not prescribed for. Do not use it for some other health conditions. Do not store the medication with an end term of its storage.